
/**
 * Added support of orthographic camera to original implementation
 * 
 * @author Eberhard Graether / http://egraether.com/
 * @author Mark Lundin 	/ http://mark-lundin.com
 * @author Simone Manini / http://daron1337.github.io
 * @author Luca Antiga 	/ http://lantiga.github.io
 */

export function CADTrackballControls( object, domElement ) {

  var _this = this;
  var STATE = { NONE: - 1, ROTATE: 0, ZOOM: 1, PAN: 2, TOUCH_ROTATE: 3, TOUCH_ZOOM_PAN: 4 };

  this.object = object;
  this.domElement = ( domElement !== undefined ) ? domElement : document;

  // API

  this.enabled = true;

  this.screen = { left: 0, top: 0, width: 0, height: 0 };

  this.rotateSpeed = 1.0;
  this.zoomSpeed = 1.2;
  this.panSpeed = 0.3;

  this.noRotate = false;
  this.noZoom = false;
  this.noPan = false;

  this.staticMoving = false;
  this.dynamicDampingFactor = 0.2;

  this.minDistance = 0;
  this.maxDistance = Infinity;

  this.keys = [ 65 /*A*/, 83 /*S*/, 68 /*D*/ ];

  // internals

  this.target = new THREE.Vector3();

  this.projectionChanged = false;
  this.projectionZoomSpeed = 0.5;

  var EPS = 0.000001;

  var lastPosition = new THREE.Vector3();

  var _state = STATE.NONE,
    _prevState = STATE.NONE,

    _eye = new THREE.Vector3(),

    _movePrev = new THREE.Vector2(),
    _moveCurr = new THREE.Vector2(),

    _lastAxis = new THREE.Vector3(),
    _lastAngle = 0,

    _zoomStart = new THREE.Vector2(),
    _zoomEnd = new THREE.Vector2(),

    _touchZoomDistanceStart = 0,
    _touchZoomDistanceEnd = 0,

    _panStart = new THREE.Vector2(),
    _panEnd = new THREE.Vector2();

  // for reset

  this.target0 = this.target.clone();
  this.position0 = this.object.position.clone();
  this.up0 = this.object.up.clone();

  // events

  var changeEvent = { type: 'change' };
  var startEvent = { type: 'start' };
  var endEvent = { type: 'end' };


  // methods

  this.handleResize = function () {

    if ( this.domElement === document ) {

      this.screen.left = 0;
      this.screen.top = 0;
      this.screen.width = window.innerWidth;
      this.screen.height = window.innerHeight;

    } else {

      var box = this.domElement.getBoundingClientRect();
      // adjustments come from similar code in the jquery offset() function
      var d = this.domElement.ownerDocument.documentElement;
      this.screen.left = box.left + window.pageXOffset - d.clientLeft;
      this.screen.top = box.top + window.pageYOffset - d.clientTop;
      this.screen.width = box.width;
      this.screen.height = box.height;

    }

  };

  this.handleEvent = function ( event ) {

    if ( typeof this[ event.type ] == 'function' ) {

      this[ event.type ]( event );

    }

  };

  var getMouseOnScreen = ( function () {

    var vector = new THREE.Vector2();

    return function getMouseOnScreen( pageX, pageY ) {

      vector.set(
        ( pageX - _this.screen.left ) / _this.screen.width,
        ( pageY - _this.screen.top ) / _this.screen.height
      );

      return vector;

    };

  }() );

  var getMouseOnCircle = ( function () {

    var vector = new THREE.Vector2();

    return function getMouseOnCircle( pageX, pageY ) {

      vector.set(
        ( ( pageX - _this.screen.width * 0.5 - _this.screen.left ) / ( _this.screen.width * 0.5 ) ),
        ( ( _this.screen.height + 2 * ( _this.screen.top - pageY ) ) / _this.screen.width ) // screen.width intentional
      );

      return vector;

    };

  }() );

  this.rotateCamera = ( function() {

    var axis = new THREE.Vector3(),
      quaternion = new THREE.Quaternion(),
      eyeDirection = new THREE.Vector3(),
      objectUpDirection = new THREE.Vector3(),
      objectSidewaysDirection = new THREE.Vector3(),
      moveDirection = new THREE.Vector3(),
      angle;

    return function rotateCamera() {

      moveDirection.set( _moveCurr.x - _movePrev.x, _moveCurr.y - _movePrev.y, 0 );
      angle = moveDirection.length();

      if ( angle ) {

        _eye.copy( _this.object.position ).sub( _this.target );

        eyeDirection.copy( _eye ).normalize();
        objectUpDirection.copy( _this.object.up ).normalize();
        objectSidewaysDirection.crossVectors( objectUpDirection, eyeDirection ).normalize();

        objectUpDirection.setLength( _moveCurr.y - _movePrev.y );
        objectSidewaysDirection.setLength( _moveCurr.x - _movePrev.x );

        moveDirection.copy( objectUpDirection.add( objectSidewaysDirection ) );

        axis.crossVectors( moveDirection, _eye ).normalize();

        angle *= _this.rotateSpeed;
        quaternion.setFromAxisAngle( axis, angle );

        _eye.applyQuaternion( quaternion );
        _this.object.up.applyQuaternion( quaternion );

        _lastAxis.copy( axis );
        _lastAngle = angle;

      } else if ( ! _this.staticMoving && _lastAngle ) {

        _lastAngle *= Math.sqrt( 1.0 - _this.dynamicDampingFactor );
        _eye.copy( _this.object.position ).sub( _this.target );
        quaternion.setFromAxisAngle( _lastAxis, _lastAngle );
        _eye.applyQuaternion( quaternion );
        _this.object.up.applyQuaternion( quaternion );

      }

      _movePrev.copy( _moveCurr );

    };

  }() );


  this.setCameraMode = function(isOrthographic) {
    this.noZoom = isOrthographic;
    this.projectionZoom = isOrthographic;
  };
  
  this.zoomCamera = function () {

    var factor;

    if ( _state === STATE.TOUCH_ZOOM_PAN ) {

      factor = _touchZoomDistanceStart / _touchZoomDistanceEnd;
      _touchZoomDistanceStart = _touchZoomDistanceEnd;
      _eye.multiplyScalar( factor );

    } else {

      factor = 1.0 + ( _zoomEnd.y - _zoomStart.y ) * _this.zoomSpeed;

      if ( factor !== 1.0 && factor > 0.0 ) {

        _eye.multiplyScalar( factor );

      }

      if ( _this.staticMoving ) {

        _zoomStart.copy( _zoomEnd );

      } else {

        _zoomStart.y += ( _zoomEnd.y - _zoomStart.y ) * this.dynamicDampingFactor;

      }

    }

  };

  this.panCamera = ( function() {

    var mouseChange = new THREE.Vector2(),
      objectUp = new THREE.Vector3(),
      pan = new THREE.Vector3();

    return function panCamera() {

      mouseChange.copy( _panEnd ).sub( _panStart );

      if ( mouseChange.lengthSq() ) {

        mouseChange.multiplyScalar( _eye.length() * _this.panSpeed );

        pan.copy( _eye ).cross( _this.object.up ).setLength( mouseChange.x );
        pan.add( objectUp.copy( _this.object.up ).setLength( mouseChange.y ) );

        _this.object.position.add( pan );
        _this.target.add( pan );

        if ( _this.staticMoving ) {

          _panStart.copy( _panEnd );

        } else {

          _panStart.add( mouseChange.subVectors( _panEnd, _panStart ).multiplyScalar( _this.dynamicDampingFactor ) );

        }

      }

    };

  }() );

  this.checkDistances = function () {

    if ( ! _this.noZoom || ! _this.noPan ) {

      if ( _eye.lengthSq() > _this.maxDistance * _this.maxDistance ) {

        _this.object.position.addVectors( _this.target, _eye.setLength( _this.maxDistance ) );
        _zoomStart.copy( _zoomEnd );

      }

      if ( _eye.lengthSq() < _this.minDistance * _this.minDistance ) {

        _this.object.position.addVectors( _this.target, _eye.setLength( _this.minDistance ) );
        _zoomStart.copy( _zoomEnd );

      }

    }

  };

  this.update = function () {

    _eye.subVectors( _this.object.position, _this.target );

    if ( ! _this.noRotate ) {

      _this.rotateCamera();

    }

    if ( ! _this.noZoom ) {

      _this.zoomCamera();

    }

    if ( ! _this.noPan ) {

      _this.panCamera();

    }

    _this.object.position.addVectors( _this.target, _eye );

    _this.checkDistances();

    _this.object.lookAt( _this.target );

    if ( lastPosition.distanceToSquared( _this.object.position ) > EPS || this.projectionChanged) {

      this.projectionChanged = false;
      
      _this.dispatchEvent( changeEvent );

      lastPosition.copy( _this.object.position );

    }

  };

  this.reset = function () {

    _state = STATE.NONE;
    _prevState = STATE.NONE;

    _this.target.copy( _this.target0 );
    _this.object.position.copy( _this.position0 );
    _this.object.up.copy( _this.up0 );

    _eye.subVectors( _this.object.position, _this.target );

    _this.object.lookAt( _this.target );

    _this.dispatchEvent( changeEvent );

    lastPosition.copy( _this.object.position );

  };

  // listeners

  function keydown( event ) {

    if ( _this.enabled === false ) return;

    window.removeEventListener( 'keydown', keydown );

    _prevState = _state;

    if ( _state !== STATE.NONE ) {

      return;

    } else if ( event.keyCode === _this.keys[ STATE.ROTATE ] && ! _this.noRotate ) {

      _state = STATE.ROTATE;

    } else if ( event.keyCode === _this.keys[ STATE.ZOOM ] && ! _this.noZoom ) {

      _state = STATE.ZOOM;

    } else if ( event.keyCode === _this.keys[ STATE.PAN ] && ! _this.noPan ) {

      _state = STATE.PAN;

    }

  }

  function keyup( event ) {

    if ( _this.enabled === false ) return;

    _state = _prevState;

    window.addEventListener( 'keydown', keydown, false );

  }

  function mousedown( event ) {

    if ( _this.enabled === false ) return;

    event.preventDefault();
    //event.stopPropagation(); - interfere with entire application

    if ( _state === STATE.NONE ) {

      _state = event.button;

    }

    if ( _state === STATE.ROTATE && ! _this.noRotate ) {

      _moveCurr.copy( getMouseOnCircle( event.pageX, event.pageY ) );
      _movePrev.copy( _moveCurr );

    } else if ( _state === STATE.ZOOM && ! _this.noZoom ) {

      _zoomStart.copy( getMouseOnScreen( event.pageX, event.pageY ) );
      _zoomEnd.copy( _zoomStart );

    } else if ( _state === STATE.PAN && ! _this.noPan ) {

      _panStart.copy( getMouseOnScreen( event.pageX, event.pageY ) );
      _panEnd.copy( _panStart );

    }

    document.addEventListener( 'mousemove', mousemove, false );
    document.addEventListener( 'mouseup', mouseup, false );

    _this.dispatchEvent( startEvent );

  }

  function mousemove( event ) {

    if ( _this.enabled === false ) return;

    event.preventDefault();
    event.stopPropagation();

    if ( _state === STATE.ROTATE && ! _this.noRotate ) {

      _movePrev.copy( _moveCurr );
      _moveCurr.copy( getMouseOnCircle( event.pageX, event.pageY ) );

    } else if ( _state === STATE.ZOOM && ! _this.noZoom ) {

      _zoomEnd.copy( getMouseOnScreen( event.pageX, event.pageY ) );

    } else if ( _state === STATE.PAN && ! _this.noPan ) {

      _panEnd.copy( getMouseOnScreen( event.pageX, event.pageY ) );

    }

  }

  function mouseup( event ) {

    if ( _this.enabled === false ) return;

    event.preventDefault();
    event.stopPropagation();

    _state = STATE.NONE;

    document.removeEventListener( 'mousemove', mousemove );
    document.removeEventListener( 'mouseup', mouseup );
    _this.dispatchEvent( endEvent );

  }

  function mousewheel( event ) {

    if ( _this.enabled === false ) return;

    event.preventDefault();
    event.stopPropagation();
    _this.zoomStep(event.deltaMode, event.deltaY);
  }
  
  this.zoomStep = function( deltaMode, delta ) {

    if (_this.projectionZoom) {
      let speed = _this.projectionZoomSpeed;
      switch ( deltaMode ) {

        case 2:
          // Zoom in pages
          speed *= 10;
          break;
        case 1:
          // Zoom in lines
          speed *= 3;
          break;
      }
      let step = Math.pow( 0.95, speed);
      if (delta < 0) {
        step = 1 / step;
      } 
      _this.object.zoom *= step;
      _this.object.updateProjectionMatrix();
      _this.projectionChanged = true;

    } else {

      switch ( deltaMode ) {

        case 2:
          // Zoom in pages
          _zoomStart.y -= delta * 0.025;
          break;

        case 1:
          // Zoom in lines
          _zoomStart.y -= delta * 0.01;
          break;

        default:
          // undefined, 0, assume pixels
          _zoomStart.y -= delta * 0.00025;
          break;

      }

      _this.dispatchEvent( startEvent );
      _this.dispatchEvent( endEvent );
    }

  };

  function touchstart( event ) {

    if ( _this.enabled === false ) return;

    switch ( event.touches.length ) {

      case 1:
        _state = STATE.TOUCH_ROTATE;
        _moveCurr.copy( getMouseOnCircle( event.touches[ 0 ].pageX, event.touches[ 0 ].pageY ) );
        _movePrev.copy( _moveCurr );
        break;

      default: // 2 or more
        _state = STATE.TOUCH_ZOOM_PAN;
        var dx = event.touches[ 0 ].pageX - event.touches[ 1 ].pageX;
        var dy = event.touches[ 0 ].pageY - event.touches[ 1 ].pageY;
        _touchZoomDistanceEnd = _touchZoomDistanceStart = Math.sqrt( dx * dx + dy * dy );

        var x = ( event.touches[ 0 ].pageX + event.touches[ 1 ].pageX ) / 2;
        var y = ( event.touches[ 0 ].pageY + event.touches[ 1 ].pageY ) / 2;
        _panStart.copy( getMouseOnScreen( x, y ) );
        _panEnd.copy( _panStart );
        break;

    }

    _this.dispatchEvent( startEvent );

  }

  function touchmove( event ) {

    if ( _this.enabled === false ) return;

    event.preventDefault();
    event.stopPropagation();

    switch ( event.touches.length ) {

      case 1:
        _movePrev.copy( _moveCurr );
        _moveCurr.copy( getMouseOnCircle( event.touches[ 0 ].pageX, event.touches[ 0 ].pageY ) );
        break;

      default: // 2 or more
        var dx = event.touches[ 0 ].pageX - event.touches[ 1 ].pageX;
        var dy = event.touches[ 0 ].pageY - event.touches[ 1 ].pageY;
        _touchZoomDistanceEnd = Math.sqrt( dx * dx + dy * dy );

        var x = ( event.touches[ 0 ].pageX + event.touches[ 1 ].pageX ) / 2;
        var y = ( event.touches[ 0 ].pageY + event.touches[ 1 ].pageY ) / 2;
        _panEnd.copy( getMouseOnScreen( x, y ) );
        break;

    }

  }

  function touchend( event ) {

    if ( _this.enabled === false ) return;

    switch ( event.touches.length ) {

      case 0:
        _state = STATE.NONE;
        break;

      case 1:
        _state = STATE.TOUCH_ROTATE;
        _moveCurr.copy( getMouseOnCircle( event.touches[ 0 ].pageX, event.touches[ 0 ].pageY ) );
        _movePrev.copy( _moveCurr );
        break;

    }

    _this.dispatchEvent( endEvent );

  }

  function contextmenu( event ) {

    if ( _this.enabled === false ) return;

    event.preventDefault();

  }

  this.dispose = function() {

    this.domElement.removeEventListener( 'contextmenu', contextmenu, false );
    this.domElement.removeEventListener( 'mousedown', mousedown, false );
    this.domElement.removeEventListener( 'wheel', mousewheel, false );

    this.domElement.removeEventListener( 'touchstart', touchstart, false );
    this.domElement.removeEventListener( 'touchend', touchend, false );
    this.domElement.removeEventListener( 'touchmove', touchmove, false );

    document.removeEventListener( 'mousemove', mousemove, false );
    document.removeEventListener( 'mouseup', mouseup, false );

    window.removeEventListener( 'keydown', keydown, false );
    window.removeEventListener( 'keyup', keyup, false );

  };

  this.domElement.addEventListener( 'contextmenu', contextmenu, false );
  this.domElement.addEventListener( 'mousedown', mousedown, false );
  this.domElement.addEventListener( 'wheel', mousewheel, false );

  this.domElement.addEventListener( 'touchstart', touchstart, false );
  this.domElement.addEventListener( 'touchend', touchend, false );
  this.domElement.addEventListener( 'touchmove', touchmove, false );

  window.addEventListener( 'keydown', keydown, false );
  window.addEventListener( 'keyup', keyup, false );

  this.handleResize();

  // force an update at start
  this.update();

};

CADTrackballControls.prototype = Object.create( THREE.EventDispatcher.prototype );
CADTrackballControls.prototype.constructor = CADTrackballControls;